Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts and first/last seen dates.

100 hosts (first page) · 198 ms

HostCertsFirst seenLast seen
fortum.pl 8 2026-04-17 2026-09-11
media.fortum.pl 4 2026-04-12 2026-08-10
energia.fortum.pl 3 2026-06-22 2026-09-10
twojaenergia.fortum.pl 6 2025-07-18 2026-09-19
www.twojaenergia.fortum.pl 5 2026-05-22 2026-09-19
dobraenergia.fortum.pl 3 2026-06-16 2026-08-31
czystaenergia.fortum.pl 3 2026-06-16 2026-08-31
silesia.fortum.pl 6 2026-04-22 2026-08-14
www.silesia.fortum.pl 6 2026-04-22 2026-08-14
marketspolska.fortum.pl 3 2026-05-28 2026-08-11
zawszerynkowacena.fortum.pl 10 2026-05-18 2026-09-13
ankieta.fortum.pl 5 2026-04-23 2026-08-21
b2b.fortum.pl 20 2026-05-18 2026-09-14
energetycznyhandlowiec.fortum.pl 3 2026-05-21 2026-08-05
zrc.fortum.pl 14 2026-05-10 2026-09-05
med.fortum.pl 4 2026-05-12 2026-07-26
prepaid.fortum.pl 6 2026-05-05 2026-10-03
przejmij-kontrole.fortum.pl 3 2026-06-10 2026-08-29
przejmijkontrole.fortum.pl 15 2026-05-13 2026-09-13
www.przejmijkontrole.fortum.pl 1 2026-05-13 2026-05-13
*.qa-online.fortum.pl 5 2025-08-11 2026-09-09
*.test-online.fortum.pl 5 2025-06-22 2026-08-25
testebok.test-online.fortum.pl 2 2025-06-22 2026-05-22
csire.fortum.pl 3 2026-05-12 2026-06-05
www.csire.fortum.pl 2 2026-05-12 2026-06-05
pradnakarte.fortum.pl 6 2026-05-05 2026-10-03
staging.fortum.pl 5 2026-05-16 2026-09-12
natwoichwarunkach.fortum.pl 1 2026-02-06 2026-02-06
drzewadlaziemi.fortum.pl 10 2026-05-18 2026-09-13
poznaj.fortum.pl 3 2026-06-22 2026-09-05
www.poznaj.fortum.pl 4 2026-04-18 2026-09-15
oszczedzaj.fortum.pl 6 2026-04-22 2026-08-14
www.oszczedzaj.fortum.pl 6 2026-04-22 2026-08-14
ebok.fortum.pl 7 2025-10-09 2026-10-06
cieplo.ebok.fortum.pl 3 2025-10-09 2026-10-06
www.cieplo.ebok.fortum.pl 3 2025-10-09 2026-10-06
www.ebok.fortum.pl 3 2025-10-09 2026-10-06
pradigaz.ebok.fortum.pl 3 2025-10-09 2026-10-06
www.pradigaz.ebok.fortum.pl 3 2025-10-09 2026-10-06
portal.fortum.pl 1 2026-01-20 2026-01-20
demo.portal.fortum.pl 1 2026-07-20 2026-07-20
polecam.fortum.pl 12 2026-05-18 2026-09-13
gazdlafirm.fortum.pl 4 2026-05-12 2026-07-31
optimum.fortum.pl 4 2026-05-21 2026-09-25
id.optimum.fortum.pl 11 2026-04-14 2026-09-23
kfn.fortum.pl 5 2026-05-05 2026-10-03
design.fortum.pl 3 2026-05-25 2026-10-06
aio.fortum.pl 1 2026-02-27 2026-02-27
eko.fortum.pl 4 2026-05-12 2026-07-26
*.cieplo.fortum.pl 4 2026-01-01 2026-08-07
monitoring-media.cieplo.fortum.pl 1 2025-12-02 2025-12-02
*.monitoring-media.cieplo.fortum.pl 1 2025-12-02 2025-12-02
*.qa.cieplo.fortum.pl 4 2026-01-01 2026-08-07
monitoring-media.qa.cieplo.fortum.pl 2 2025-12-02 2026-08-03
*.monitoring-media.qa.cieplo.fortum.pl 2 2025-12-02 2026-08-03
ekam-stage.qa.cieplo.fortum.pl 1 2025-07-17 2025-07-17
www.ekam-stage.qa.cieplo.fortum.pl 1 2025-07-17 2025-07-17
monitoring.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.monitoring.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.internal.qa.cieplo.fortum.pl 1 2026-02-09 2026-02-09
individual-settlements.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.individual-settlements.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
kontakt.qa.cieplo.fortum.pl 2 2025-09-19 2026-08-20
*.kontakt.qa.cieplo.fortum.pl 2 2025-09-19 2026-08-20
monitoring-media-preview.qa.cieplo.fortum.pl 2 2025-12-02 2026-08-03
*.monitoring-media-preview.qa.cieplo.fortum.pl 2 2025-12-02 2026-08-03
monitoring-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.monitoring-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
individual-settlements-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.individual-settlements-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
kontakt-preview.qa.cieplo.fortum.pl 3 2025-09-19 2026-08-20
*.kontakt-preview.qa.cieplo.fortum.pl 3 2025-09-19 2026-08-20
monitoring-media-amplify-preview.qa.cieplo.fortum.pl 1 2026-04-17 2026-04-17
*.monitoring-media-amplify-preview.qa.cieplo.fortum.pl 1 2026-04-17 2026-04-17
bonifikaty-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.bonifikaty-preview.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
monitoring-media-amplify.qa.cieplo.fortum.pl 1 2026-04-17 2026-04-17
*.monitoring-media-amplify.qa.cieplo.fortum.pl 1 2026-04-17 2026-04-17
bonifikaty.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.bonifikaty.qa.cieplo.fortum.pl 1 2026-01-29 2026-01-29
monitoring.cieplo.fortum.pl 1 2026-02-04 2026-02-04
*.monitoring.cieplo.fortum.pl 1 2026-02-04 2026-02-04
*.internal.cieplo.fortum.pl 1 2025-12-10 2025-12-10
dsr.cieplo.fortum.pl 1 2026-02-04 2026-02-04
*.dsr.cieplo.fortum.pl 1 2026-02-04 2026-02-04
individual-settlements.cieplo.fortum.pl 1 2026-02-04 2026-02-04
*.individual-settlements.cieplo.fortum.pl 1 2026-02-04 2026-02-04
kontakt.cieplo.fortum.pl 2 2025-09-19 2026-08-20
*.kontakt.cieplo.fortum.pl 2 2025-09-19 2026-08-20
start.cieplo.fortum.pl 2 2026-01-22 2026-06-13
*.test.cieplo.fortum.pl 5 2026-01-01 2026-07-03
monitoring-media.test.cieplo.fortum.pl 1 2025-12-02 2025-12-02
*.monitoring-media.test.cieplo.fortum.pl 1 2025-12-02 2025-12-02
monitoring.test.cieplo.fortum.pl 1 2026-02-10 2026-02-10
*.monitoring.test.cieplo.fortum.pl 1 2026-02-10 2026-02-10
*.internal.test.cieplo.fortum.pl 1 2026-02-09 2026-02-09
dsr.test.cieplo.fortum.pl 1 2026-01-29 2026-01-29
*.dsr.test.cieplo.fortum.pl 1 2026-01-29 2026-01-29
individual-settlements.test.cieplo.fortum.pl 3 2026-04-16 2026-09-16
*.individual-settlements.test.cieplo.fortum.pl 3 2026-04-16 2026-09-16

Showing the first 100 hostnames — sign in with GitHub or Google to page the full list, or use the API with an API key: GET /v1/hosts/fortum.pl.

Shown here: hostnames with a certificate that is valid now or expired within the last 90 days. The full history since 2013 — hostnames whose last certificate expired earlier — is a Pro plan method: GET /v1/hosts-history/fortum.pl.